Amazing new 18650 cells for E-bike batteries in 2015

The new 18650-format cells that are just now becoming available are an exciting milestone that changes everything in the high-performance E-bike world. Back in 2013, we wrote about the trend of E-bikes using 18650 cells with the NMC and NCA chemistry. In 2014, we wrote about the recent availability of high-current cells (so you didn’t have to use LiPo for high performance). Well, now…in 2015, the story to know is about medium and high-current 18650 cells from a variety of sources, that have a higher capacity.

18650 = 18mm in diameter, 65mm long.

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What about LiPo?

Batteries have been the biggest performance hold-up in the electric bike world…until now! Before I get started, I know some of you will think I am forgetting about LiPo. I’ve used LiPo before, I own LiPo right now, and trust me when I say…LiPo will never catch on with the general public. LiPo is for high performance enthusiasts, but…the charging systems are too cluttered and complex, and although many LiPo users can assemble a pack together cheaper than a pack made from 18650 cells, a LiPo pack that is used daily to a full discharge/charge cycle will likely only last for one years riding season.

If you want to argue that you have managed to get a couple years out of a LiPo pack, I am happy for you, but…just try to sell a LiPo pack that is one year old. Nobody wants it. What Battery Management System (BMS) did you use? (if the pack even has a BMS). LiPo packs use soft-sided flat foil cells, so anyone who wants to “save money” by using LiPo has to build a protective housing.

For every E-bike enthusiast who assembles a LiPo pack and charging system, there are hundreds who will never go to the effort of building one, and they just want to buy a battery and a simple charger. I can’t find anyone I trust who is selling complete 12S / 15-Ah LiPo packs and charging systems with a cell-balancing capability.

LiPo is here to stay (for racing), but…once you factor in how a quality 18650-cell pack will last for several years of daily use, any cost benefit you thought LiPo had…it just doesn’t pan out.

Side note: for those jobs where you still want to use LiPo for an E-bike, the large-format Hobby King Multistar brand is popular right now.

Hobby King Multistar Lithium Polymer (LiPo). This single brick is 16-Ah at 6S. If you wanted 12S (44V) you’d only need two of them, and for 18S (72V), it is only three of them.

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The Samsung 25R cell

Last summer, in 2014, Samsung made a real splash in the E-bike DIY world when they began selling the 20R cell. It is rated as a 22A cell, so if you made a pack out of parallel strings that each use five cells (5P), that pack could put out 110A! This was the turning point when garage builders had a real choice between LiPo or something else. The 20R cell got a lot of garage builders to buy a spot welder.

Of course, there was a downside. The “20” in the name 20R meant that this cell only had 2000-mAh of range. When you series a group of paralleled cell-strings, it raises the voltage of the pack, but…everything you need to know about a battery packs range and total amp-producing capability is in the parallel sub-packs.

A 5P string of 20R cells (capable of 110A peaks) would make a pack that only had 10-Ah of range. For a common 12S pack (around 44V), that would mean you’d only need 60 of the 18650 cells. As you can imagine, 60 of the 18650 cells are not hard to fit onto just about any bicycle frame, but…having only 10-Ah of range is not enough for most riders.

All of this is an issue because E-bikes don’t have a lot of space to mount battery packs. When thinking about compromises, should you sacrifice range to get high amps?…or do you sacrifice high performance to be able to get a decent amount of range?

E-bikers who are happy with a simple commuter using 36V are not the kind of people who spend time reading articles about the cells in the battery pack…they just want something that they can plug it in and it works when they want to take it out for a spin. This article is focused at DIY kit builders who want to use between 12S to 18S system voltages (44V-72V), but they want to avoid using LiPo on their daily driver E-bike.

This year is the turning point for E-bikers who want an easy and reliable battery pack with good performance, long life, and still have decent range. Samsung (in S. Korea) is one of the top players in the 18650 cell world. They decided to release a cell that had 20% more range than the 20R cell, but only had to give up a small amount of its ability to crank out the amps.

Whether you are spot-welding your own pack, or buying a pack built by a company, 18650’s have completely taken over the electric bike world due to performance, cost, and safety.

The 25R cell has 2500-mAh of range, but still is able to produce 20A of current. This means a 5P string can produce peaks of 100A (more than enough for the E-bikers I am writing for), and!…a 60-cell 12S / 5P pack will have 12.5-Ah of range. That doesn’t sound like a huge improvement, but with mid-drive systems getting very good range per watt-hour (WH), an extra 2.5 Amp-hours (Ah) in the pack can go a long way.

E-bike battery packs made from the 25R cell are available right now. If I was buying a battery pack for a hot rod ebike today, this is what I’d get.

So, following this logic…meaning that if we give up a little bit of the max current to get more range, how far can we take that? Samsung has already answered that question for those of you who might be curious.

Right now (summer of 2015) you can buy loose/individual (New In Box/NIB) Samsung 30Q cells, but there are no E-bike battery packs from these…yet (but they are coming soon). Like the name implies, these cells have 3000-mAh per cell, so a 5P string provides an impressive 15-Ah, and you can get that from a very small 60-cell pack if it is configured for 12S. If you wanted to go up to 18S (around 72V when fully charged), you would need to fit 90 cells into a pack somewhere on your bike.

So…how much current do we have to give up to get 15-Ah from a small 60-cell pack? the Samsung 30Q cell is rated for 15A per cell, so a 5P string still provides 75A peaks. In my humble opinion, this is the turning point for E-bike batteries. There will still be some users who want more amps or more range, but there have been a lot of potential E-bike buyers who have been holding off due to low performance, short range, and high prices.

Prices will come down in time, but when it comes to a plug-and-play battery pack that has both high performance and long range in a small package (plus it will last for years)…the tipping point is here right now. Here’s a peek: The upcoming Samsung 35E cell has 3500-mAh and we feel it safely provides 9A per cell. Our theoretical 60-cell 12S / 5P pack made from the 35E would give you 45A with 17.5-Ah of range!

Now that I’ve made a case for 18650 cells that can provide at least 10A per cell, and still have at least 3000-mAh of range, what has Panasonic and LG been doing? Sitting around scratching their heads?

Last year when Samsungs newest high performance cell made its debut (the 25R), Panasonic introduced more range instead of more current. They developed their now-famous “B” cell (3400-mAh Panasonic NCR18650B), which was the result of Panasonics relationship with the Tesla electric car company.

For a high performance E-bike pack, the expensive and well-known Sony VTC family has been the cell of choice in the past for several years, but…now?

The VTC3 was a 30A cell with 1600-mAh, and that was the “safe” alternative to LiPo five years ago. They then came out with the VTC4, which boosted their range to 2100-mAh per cell (this is when I started to see more E-bike battery packs made from Sony “Konion” cells). Recently they introduced the VTC5 cell, which has 2500-mAh of range, but even though many places list them as a 30A cell, they actually get very hot at 30A, and they only perform well at 20A per cell. That would put them in the same general performance class as the Samsung 25R, and even though they are very expensive (compared to the other choices), the real problem with Sony cells is something completely unexpected…

A huge earthquake rocked northern Japan, which led to a very destructive Tsunami (tidal wave), and directly led to the Fukushima nuclear power plant disaster. All of this damaged Sony’s nearby main VTC cell factory (and restricted electrical use for the region). At that time, there were millions of authentic VTC cells in warehouses across the globe, with many of them contracted to go into Makita cordless tools.

In order to continue to service their existing supply contracts, Sony began having their VTC cells made in the Philippines and China. The problem right now is…a shockingly high percentage of Sony VTC cells are being found to be counterfeits.

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What happened to Sanyo?

Sanyo is actually one of the largest battery makers in the world, due to all of the consumer products that they directly or indirectly make. Cordless phones, cell phones, cordless tools, laptop computer batteries, etc

For whatever reason, Panasonic purchased control over Sanyo’s 18650 cell operations. Every Sanyo product that is using 18650 cells is being upgraded to new versions, even if only to make the products run longer (at the same number of amps). Sanyo products that used 18650’s will now be upgraded to the appropriate Panasonic cell, except…Sanyo had one new model of cell in particular that is exceptional (all the named manufacturers are constantly experimenting and patenting improved batteries). That cell is now called the Panasonic-Sanyo 18650GA, 3400-mAh, 10A (more on this cell below)…

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Current vs Capacity

The developments over the last year have resulted in products that are a real milestone for electric bikes. Look carefully at these three Samsung cells, and the capacity along with the current they can put out safely, and see the relationship between the two:

20A__2500-mAh___25R

15A__3000-mAh___30Q

10A__3500-mAh___35E

New technology has dramatically increased the capacity of these 18650 format cells, but the more current you want, the less capacity they can hold. The three cells listed here are all from the same company, using the same chemistry.

New-In-Box/NIB 18650 cells.

There has been such a huge explosion of cell varieties in the common-performance types, that there’s not enough room to list them here. Plus, I’m not interested in them. There are hundreds of retailers selling common-performance battery packs in 5P that provide 20A (4A per cell), and they compete on lowest price.

I am going to list several models of 18650 cells below that I think will soon become available to build battery packs from, and that I believe will become the most desirable cells to use on an E-bike.

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Highest Current

The first group I want to tell you about has three models, and they are all are from South Korea.

I’m not mentioning price because…prices on new products are high, the prices will come down in time, and prices vary from one supplier to another.

That being said…these cells are the current replacement for LiPo in high performance E-bikes. All three are rated for 20A continuous per cell (and some web-sites list their temporary peak capabilities at around 35A!). I am reluctant to list peak amps, because…the few places that do that do not agree on the amount, and they don’t list for how long the “peak” amp-draw is, or what temperatures they reached before they stopped raising the amp-draws.

With either of these cells, a tiny 5P pack (only 60 cells if configured for 12S/44V) can put out 100A! If you are only drawing 60A as a peak during acceleration, and maybe 20A during a cruise-phase…a pack like this will not even get warm, and should last a very long time.

[The new Sony VTC6 has 3100-mAh of capacity, and provides 30A, but…the market has been flooded with counterfeits. If you want these, you have to go back to gutting authentic Makita cordless drill packs]

3000-mAh, 20A, ICR18650HG2, LG-Chem

2500-mAh, 20A, INR1865025R, Samsung

2500-mAh, 20A, ICR18650HE4, LG-Chem

2017 edit: if you really don’t care about range or length of life, and you want to get very high amps from a very small pack, the high-amp 18650 kings are these two:

2100-mAh, 30A, Sony VTC4, US18650VTC4

1500-mAh, 30A, LG HB6, LGDAHB61865

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High Current with More Capacity

In the example above, a 60-cell 12S/5P pack of 2500-mAh cells would have 12.5-Ah of range. But…what if you wanted more range than that, and you didn’t need 100A of acceleration? The cell choice in this category is the Samsung-SDI 30Q cell. It has 20% more capacity, and yet it still puts out 15A per cell. A battery pack that is a 12S / 5P would have a useful 15-Ah of range, but still put out 75A continuous.

The Samsung 30Q is an exciting cell, but…I think most hot-rodders can be happy with even fewer amps if it means even more range in a tiny battery pack.

3000-mAh, INR1865030Q, Samsung

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MAX Capacity that still has Great Current

There are several new cells in this category that will just plain transform what builders understand about what is possible in a tiny high-performance battery pack. With 10A of current per cell, a 5P pack can provide 50A continuous, but at a higher capacity. It would be reasonable to expect temporary 75A peaks from a 50A continuous pack, as long as there were frequent cruise-phases when you were only drawing 20A to maintain your top speed, so the pack could cool down.

The 10A per cell options are:

3500-mAh, NCR18650GA, Panasonic-Sanyo

3500-mAh, INR18650MJ1, LG-Chem

3200-mAh, NCR18650BD, Panasonic

3200-mAh, INR18650MH1, LG-Chem

2900-mAh, NCR18650PF, Panasonic

(out of the 10A cells listed, the PF is turning out to be the most affordable choice from most suppliers. Plus, this last year it has proven to truly perform well at an actual 10A per cell)

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EDIT, a 2016 re-evaluation of a couple of these cells

3500-mAh, INR1865035E, Samsung

All the information I had available in 2015 indicated this was a 10A cell. It has a higher capacity, but for long life, I am now calling this a 6A cell. Its a good cell, just not able to put out 10A continuous without getting hot.

3400-mAh, NCR18650B, Panasonic

Same story here. This is a great cell, but for long life and the battery not getting too hot? Limit it to 6A per cell. This is the cell used by the Tesla car company in 2015.

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Some Conclusions

If you can fit a large battery pack in your frame, you don’t need to pay top dollar for the high-current 25R,HE4, HG2, or 30Q cells to get high amps out of the pack. As an example, if you increase the parallel strings from 5P to 6P, and you use the high capacity 3500-mAh GA cell, a 12S / 44V pack at 6P will give you an incredible 21-Ah of range, and it will do that with only 72 cells! A 6P pack of GA cells at 11A per cell would be 66A continuous, and peaks at roughly 90A.

You can take that same 72-cell volume of GA cells, and if configured for an 18S (72V) pack, it will have a 4P arrangement that still provides 14-Ah of range. Not bad!

This is what 100 of the 18650 cells looks like, and how they would fit.

In the pic above, these 100 cells are being “dry fit” to ensure they will all work in this small frame (before spot-welding the nickel strips to form series/parallel groups). If configured for 5P with the GA 10A cells, it would have 17.5-Ah of range, 55A continuous (70A peak?), but the real news is…100 cells would also get a pack at 20S. That means 82V when fully charged.

Or…96 cells can mean a 12S / 44V pack, with an incredible 8P, which would result in a 28-Ah ‘s of range and 88A of continuous current (120A peak?)

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Some Warnings

Be aware, when I say the GA cell is a 3500-mAh cell that provides 10A, you can have one or the other. This goes for all the cells listed above. If you calculate the range you need so you can build the smallest possible pack, and then you hit the throttle hard and often to get max amps, the pack will not deliver the full rated range. The rated capacities of all of these cells are tested in a lab at a 2A per cell drain, or less.

If you begin shopping for loose individual 18650 cells, and you find advertisements for 4200-mAh cells that put out 30A per cell…they are lying (Trustfire, Ultrafire, etc). An authentic Ultrafire cell is not horrible, but again, there are lots of counterfeits.

Buy some samples of the cell you think you want to use. Set-up a current-drain pulling the same watts that the cell is rated for, and…if it is too hot to hold in your hand after 5 minutes, its a fake. It may even look exactly like an authentic Samsung, Panasonic, or LG cell. Once you find a trusted vendor, only buy cells from them.

The Soshine SC-S7 charger for testing 18650 cells. 54-mAh means this cell is a fake, with a tiny 4.2V battery inside an 18650 shell, with an accurate-looking wrapper.

Once the test-sample cells are drained to 3.0V, charge it with 1A on a data-logging charger like the Soshine, and once the cell reaches 4.2V, the charger will tell you how many mAh went into it. It won’t be close, because either it will provide the rated capacity, or it will be way off.

Grew up in Los Angeles California, US Navy submarine mechanic from 1977-81/SanDiego. Hydraulic mechanic in the 1980's/Los Angeles. Heavy equipment operator in the 1990's/traveled to various locations. Dump truck driver in the 2000's/SW Utah. Currently a water plant operator since 2010/NW Kansas

28 Comments

JollyRoguer

( July 12, 2015 )

Paul at EM3ev is selling packs with the 25R cells in them. He makes a triangle pack version which is quite nice…all the connections and wiring are top-notch. Ron, question: how would you rate the longevity of these cells, assuming careful use? I mean shelf life/years, not cycle discharges. (Paul’s charger allows a 90% charge, and a 50% maintenance mode). What if only one cell goes bad for random reasons, does that jinx the whole pack?

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spinningmagnets

( October 7, 2017 )

Paul and Luna also sell packs with the 30Q cell. Unscientific field reports indicate the 30Q cell has a much better length of life than the 25R cell. Always charge to 4.1V per cell or less. If one cell fries (regardless of vendor) the BMS will throw a fault.

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Zachary E. Mohrmann

( July 13, 2015 )

I am more confused then I have ever been, and I guess that is why I shy away from electronics… I try to just sit back and read all I can read with out bothering anyone, and not asking any questions so as not to annoy any one… But I just am so confused with all the battery packs and li-po v’s cell packs and God knows what else, I need to ask, Is there a Book For Dummies like me, so maybe I may have a shot a doing my thing being green…? My children say that I am to old fashioned, and make fun of me because I use gas engines still… There’s just so much to just powering a trike electronically, that I just don’t understand… I apologize to anyone, if I am out of order asking this here but I don’t know where to turn…. Thanks… Zack

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Exodia

( July 30, 2015 )

Might be late, but if someone reads this: a) ask any questions on the endless sphere forums. b) dont worry about batteries so much. The expensive 18650s are simply more reliable and can sustain higher Amp draw. Where I am at, LiPos are expensive. They also have higher discharge rates tho. If you dont need a high power setup, this does NOT worry you. Buy a prebuilt pack(more expensive) or DIY( learn about electrics) a small,cheap 18650(cheap chinese will do) pack. You really dont have to go through a book for you to understand this, dont worry, read online,and ask on endless-sphere.

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Zachary E. Mohrmann

( August 1, 2015 )

Thank you so much for answering me, I tried to figure out the technological aspects of this whole battery operated motors thing for a while now.. I still use gas for my RC planes, and my nephew says I am to old fashion that I need to move to the green technology, and to stop using gas power for all the motors I use… I understand the need to go green and I think it is a good idea, But I am no electrical wizard…! I have started to change out all my yard tools, lawn mower, blower, hedger, and now my new bike that I will be ordering next month… The lawn and garden tools were easy, because they are all plug and play as my nephew says.. I am looking for a power source for the bike but am confused as to which batteries are best, and then how to put them together properly so as not to burn out the motor when I mount it to the bike.. And those motors are not cheep, so I don’t want to create a money pit.. I will be using a motor drive from Da Vinci motor drives and a 3220 motor from Astro Flight, I understand that a gentleman there is a pioneer of electrical motors of sorts, when it comes to electrical motors and drives.. So I am hoping to tap his wisdom sort speak as well.. I am all ears, and I’m willing to learn so please do share with me anything that may be helpful…! And Thanks again….!

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Exodia

( August 3, 2015 )

I wouldn’t say your motor choice is right for you. Pick a decent hub motor ( there are guides on this side on what to choose). I responded to Harry as well, but I’ll say it again: Do not worry about the specifics. Buy a pre-made pack with the Voltage that your motor needs. More AmpHours=more mileage. You really don’t need to look at single 18650 cells and what their performance is, if you can just buy a pre-assembled pack. If you have specific questions, its better to ask them in a forum then on a comment section imo.

Letsgoharry Müller

( August 2, 2015 )

Dear Exodia
For YOU and all the PRO’s it may be easy. But for us who has absolutely “no clue” about electricity, amp, discharge rate, volts, amphours, amp draw etc. it is a Book with many locker!

All this forums posts are just to high for a absolut beginner.

To speak for me: What I need is a “Friend” who understand this and Licke to help me to evuluate the “Right” parts….
But I not know any body who could do that! And I just come over to Davis,Ca to build here my VM-Camper.

Who knows … maybe somewhere out there is a “Soul” who hear my call and take the time to corespondent with me the whole matter ! ? ! ? ! ?

God bless you .. Harry

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Exodia

( August 3, 2015 )

Dear Harry,
I might have given the wrong impression here, but I am not a pro.
I am currently refining my first E-Bike build. Everything I did not know(what does 1C mean? What is 12S3P?) I figured out in a few days.

Don’t take this the wrong way, but if you do not know what Ampere or Volts mean, building your own battery might not be the right thing for you.

For people like you that just want a DIY E-Bike, yet have no grip on electronics, I would suggest these steps:
1) Find the motor you want.(read reviews, find out what power you need)
2) Read the motors description and find its voltage.
3) Find a pre-made battery pack with that voltage.
4) Check if you need additional parts, like Controller or throttle/sensors.
5) Post your component list in the appropriate forums and ask for someone to take a look. (endless-sphere or your regional equivalent)
6) Buy

If you really want to use a custom e-bike, you shouldn’t be afraid of knowing what a “Volt” is. Read wikipedia and use google, it’s really not that hard to find out.
And if you are still confused, post _specific_ questions in your favourite forum.

Best Regards,
Exodia

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Letsgoharry Müller

( August 2, 2015 )

Hello Zack
I feel the same as I would like to make my new 2 seater Velomobile-Camper with BB-Engine and Solar cells, but not know how to ask what I need for Solarcells and Batteries etc. for my Project!
All the PRO’s say… it’s Easy… but this “Easy” is just for Pros. and not for not electric-gurus like me.
Even this blog here is writen for those who already understand the whole mater… not me 🙁 … (And You????)
Hope for you you get your answers you need and understand.
For me all the answer till now was not helpful at all (Just “TO HIGH”)
Good luck with your project.
Harry

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Zachary E. Mohrmann

( September 4, 2015 )

No…! I’m still pretty much still confused over the whole thing, and I already spent a ton of money, finding out I was totally of course and heading over the falls… It seams the harder I try to understand electric motors and battery power, the more confused I get… I think I’m just going to have to have a power pack, motor drive, and lastly the drive system to get them all working to gather from some one who builds them I just pray I don’t need to hack up my frame and have it reconfigured in order to make it all work together.. I think if it gets that far out of hand I’m just going to go back to the trusty old robin gas engine and break it down and rebuild to suit my purpose, and get the max out of my engine as well
Armadillozack

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Dumbkoff

( December 30, 2015 )

Why don’t you get a cheap used scooter or e bike and learn the basics maintaining it? You can get one for a few hundred and learn electronics the way you learned car mechanics. Get your hands dirty. Worry about a customised world beater later!

( July 17, 2015 )

This was exactly what I needed to learn for my eBike build. This was a whole bunch about building an optimal battery pack. Thank you for sharing your insight on these batteries and their potential <- oh that works on multiple levels. hehe

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Ed Williams

( August 2, 2015 )

Super article! Thanks! One element that is still confusing and which needs to be thoroughly understood if you want to build your own packs is charging, especially charging packs that are series/parallel combinations. Building packs that had both series and parallel cells something I was always warned away from with standard LiPo packs but your article (and the 2013 one) make it look like this is routine with 18650s. Is 18650 inherently safer to go series/parallel with or is the technique for doing so with any Lithium based battery simply better understood now? If you could point me to some sites where I could read about this aspect in detail I would be hugely appreciative. BTW, the packs I need to build are for underwater use to power long term instruments at only a few amps. But another important issue arises trying to charge a battery in a sealed pressure vessel — generation of hydrogen gas, which is so good at going boom. Do you know anything about how 18650 battery chemistry handles this (better or worse)? I know hydrogen generation is worse the faster you push the charging — I have the option to charge very slowly if needed. Thanks!

Zachary E. Mohrmann

( August 10, 2015 )

Thank you Harry…! I am still wandering in the dark, looking for that light at the end of this tunnel.. Maybe I am just on the wrong website, But I was told I would get the help from some folks here, by another group blog… Or maybe they didn’t want to help me either and just passed the buck off by sending me here.. What ever, I gotten the same out come here as else.. It used to be sights like this that folks would love to help you, but that is becoming a lore of the past.. All I can do is keep looking for some one who will direct me in the correct direction, and pray for it not to be another dead end… Or maybe I am just not supposed to make the transition to clean energy and continue to use my old trusted gasp and choke petroleum motor…! LoL…!

( May 9, 2016 )

Chas58

( May 11, 2016 )

I’ve tried for a year to get a pack with one of these batteries, but no one sells one that I could find. I did get em3ev to build me one with Samsung SDI INR18650-32E which are a step up from the typical cell sold in 2015

( March 17, 2018 )

• EBL 3.7 Volt Li-ion 26650 Rechargeable Batteries, 5000mAh 4 Pack
• The battery is low self discharge makes itself still maintain 75% of capacity after 3 year of non-use.
• The battery can be recharged up to 1200 times when fully or partially drained.
• High recharge and discharge rate performance for you high powered device.

Brian Van

( May 6, 2018 )

I want to put together a 72v 30ah battery pack using Sanyo ncr20700A , for a 3000w hub motor, looking at 20s3p or 20s4p, controller is somewhat 12mosfet 60a 90v , motor is 30a continuous , the tests say these 2070’s are great at 10a continious ,, and good at 20a continuous, wondering if the bigger battery 4p 80cell would be too much for the system or good to give me those extra miles of riding time

( July 11, 2018 )

Using so many cells is just asking for problems. What are you going to do to when one or two of your cells fail? This will definitely happen when you have 130 cells for a 48v 20ah battery. Not to mention the nightmare of wiring for a balance charger for so many cells. 18650 is just too small of a cell for electric bike applications. There are single series lifepo batteries than can reach 48v 20ah and that’s the sort of thing I’m interested now.